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1.
Front Physiol ; 11: 160, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32161553

RESUMO

In elite sport, the Athlete Biological Passport (ABP) was invented to tackle cheaters by monitoring closely changes in biological parameters, flagging atypical variations. The hematological module of the ABP was indeed adopted in 2011 by World Athletics (WA). This study estimates the prevalence of blood doping based on hematological parameters in a large cohort of track and field athletes measured at two international major events (2011 and 2013 WA World Championships) with a hypothesized decrease in prevalence due to the ABP introduction. A total of 3683 blood samples were collected and analyzed from all participating athletes originating from 209 countries. The estimate of doping prevalence was obtained by using a Bayesian network with seven variables, as well as "blood doping" as a variable mimicking doping with low-doses of recombinant human erythropoietin (rhEPO), to generate reference cumulative distribution functions (CDFs) for the Abnormal Blood Profile Score (ABPS) from the ABP. Our results from robust hematological parameters indicate an estimation of an overall blood doping prevalence of 18% in 2011 and 15% in 2013 (non-significant difference) in average in endurance athletes [95% Confidence Interval (CI) 14-22 and 12-19% for 2011 and 2013, respectively]. A higher prevalence was observed in female athletes (22%, CI 16-28%) than in male athletes (15%, CI 9-20%) in 2011. In conclusion, this study presents the first comparison of blood doping prevalence in elite athletes based on biological measurements from major international events that may help scientists and experts to use the ABP in a more efficient and deterrent way.

2.
Br J Sports Med ; 51(17): 1309-1314, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28673896

RESUMO

OBJECTIVE: To describe and characterise serum androgen levels and to study their possible influence on athletic performance in male and female elite athletes. METHODS: 2127 observations of competition best performances and mass spectrometry-measured serum androgen concentrations, obtained during the 2011 and 2013 International Association of Athletics Federations World Championships, were analysed in male and female elite track and field athletes. To test the influence of serum androgen levels on performance, male and female athletes were classified in tertiles according to their free testosterone (fT) concentration and the best competition results achieved in the highest and lowest fT tertiles were then compared. RESULTS: The type of athletic event did not influence fT concentration among elite women, whereas male sprinters showed higher values for fT than male athletes in other events. Men involved in all throwing events showed significantly (p<0.05) lower testosterone and sex hormone binding globulin than men in other events. When compared with the lowest female fT tertile, women with the highest fT tertile performed significantly (p<0.05) better in 400 m, 400 m hurdles, 800 m, hammer throw, and pole vault with margins of 2.73%, 2.78%, 1.78%, 4.53%, and 2.94%, respectively. Such a pattern was not found in any of the male athletic events. CONCLUSION: Female athletes with high fT levels have a significant competitive advantage over those with low fT in 400 m, 400 m hurdles, 800 m, hammer throw, and pole vault.


Assuntos
Androgênios/sangue , Atletas , Desempenho Atlético , Atletismo , Adulto , Feminino , Humanos , Masculino , Espectrometria de Massas , Globulina de Ligação a Hormônio Sexual/análise , Testosterona/sangue , Adulto Jovem
4.
J Clin Endocrinol Metab ; 99(11): 4328-35, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25137421

RESUMO

OBJECTIVE: Prior to the implementation of the blood steroidal module of the Athlete Biological Passport, we measured the serum androgen levels among a large population of high-level female athletes as well as the prevalence of biochemical hyperandrogenism and some disorders of sex development (DSD). METHODS AND RESULTS: In 849 elite female athletes, serum T, dehydroepiandrosterone sulphate, androstenedione, SHBG, and gonadotrophins were measured by liquid chromatography-mass spectrometry high resolution or immunoassay. Free T was calculated. The sampling hour, age, and type of athletic event only had a small influence on T concentration, whereas ethnicity had not. Among the 85.5% that did not use oral contraceptives, 168 of 717 athletes were oligo- or amenorrhoic. The oral contraceptive users showed the lowest serum androgen and gonadotrophin and the highest SHBG concentrations. After having removed five doped athletes and five DSD women from our population, median T and free T values were close to those reported in sedentary young women. The 99th percentile for T concentration was calculated at 3.08 nmol/L, which is below the 10 nmol/L threshold used for competition eligibility of hyperandrogenic women with normal androgen sensitivity. Prevalence of hyperandrogenic 46 XY DSD in our athletic population is approximately 7 per 1000, which is 140 times higher than expected in the general population. CONCLUSION: This is the first study to establish normative serum androgens values in elite female athletes, while taking into account the possible influence of menstrual status, oral contraceptive use, type of athletic event, and ethnicity. These findings should help to develop the blood steroidal module of the Athlete Biological Passport and to refine more evidence-based fair policies and recommendations concerning hyperandrogenism in female athletes.


Assuntos
Androstenodiona/sangue , Atletas , Sulfato de Desidroepiandrosterona/sangue , Hiperandrogenismo/epidemiologia , Testosterona/sangue , Adolescente , Adulto , Feminino , Humanos , Hiperandrogenismo/sangue , Ciclo Menstrual/sangue , Pessoa de Meia-Idade , Prevalência , Globulina de Ligação a Hormônio Sexual/metabolismo , Adulto Jovem
5.
Bioanalysis ; 4(13): 1633-43, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22831479

RESUMO

The 2011 International Association of Athletics Federation (IAAF) World Championships took place in Daegu, Korea. For the first time, all athletes were blood tested prior to the competition in order to give a clear signal to the world athletic community of the wish to enter into the era of the Athlete Biological Passport and fight against doping in their sport. The hematological parameters were measured on site. Thus, a mobile-accredited laboratory for blood testing was created in Daegu. Two serum tubes were collected for clinical chemistry and hormonal analyses in order to build the bases of the endocrine and the androgen (steroid) modules of the Athlete Biological Passport in blood. This paper describes some of the main challenges the project faced with regard to the large number of athletes, competing in different disciplines, and the logistic problems that had to be solved for smart implementation of one of the most complex operations organized in the last decade in the fight against doping.


Assuntos
Atletas , Dopagem Esportivo/prevenção & controle , Testes Hematológicos/normas , Agências Internacionais/normas , Laboratórios/organização & administração , Esportes , Anabolizantes/sangue , Androgênios/sangue , Análise Química do Sangue/instrumentação , Análise Química do Sangue/normas , Feminino , Hematínicos/sangue , Hormônio do Crescimento Humano/sangue , Humanos , Masculino , Detecção do Abuso de Substâncias/normas
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